1. Field of the Invention
The invention pertains to the field of electrical relays. More particularly, the invention pertains to miniaturized parallel contact relays using linearly moving armatures.
2. Description of Related Art
The electrical contact used in a large number of currently available relays and switches produces high contact resistance. In order to facilitate high current capabilities a large contact force is usually applied, therefore a robust solenoid is required. There is a need to improve the electrical contact to allow a reduction of the size of the relay or switch while maintaining the high current capabilities.
The limit of size reduction is to fabricate the relays and switches by using MEMS processes. Presently available relays and switches at the MEMS size scale can only handle signal switching. Low contact resistance is beneficial also for the interest of minimizing heat generation. Otherwise a suitable heat sink is required which makes the size of the system larger.
Examples of previously patented electrical relays which used linear-moving armatures include U.S. Pat. No. 803,486 “Magnetically Operated Switch”, U.S. Pat. No. 2,569,776 “Electric Switch”, U.S. Pat. No. 3,194,920 “Electrical Contactor”, U.S. Pat. No. 4,041,426 “Miniature armature relay”, U.S. Pat. No. 4,509,027 “Current operated miniature relay”, U.S. Pat. No. 5,394,128 “DC vacuum relay device”, U.S. Pat. No. 5,844,457 “Electromagnetically operated electric switching apparatus” and U.S. Pat. No. 7,145,422 “DC relay”. Reed relays, which comprise small, light contacts sealed in glass tubes, acted upon directly by electromagnets, have been used in the past for high-speed switching, but such relays are limited in their current handling abilities.
The present inventor has a number of issued patents and a published patent application on electrical contacts and connectors which use, among other things, braided contacts as might be used in the present invention. These patents, incorporated herein by reference, include:    U.S. Pat. No. 7,014,479, “Electrical Contact and Connector and Method of Manufacture”    U.S. Pat. No. 7,029,288, “Electrical Contact and Connector and Method of Manufacture”    U.S. Pat. No. 7,029,289, “Interconnection Device and System”    U.S. Pat. No. 7,040,902, “Electrical Contact”    U.S. Pat. No. 7,358,603, “High Density Electronic Packages”    US Published Patent Application 2006/094,269 “Electrical Contact and Connector and Method of Manufacture”